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Old 02-14-2011, 06:22 PM   #114 (permalink)
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Originally Posted by cfg83 View Post
Frank -

I did an overlay :

NOTE: My image may be incorrect if my choice for "apex/center of camber" is incorrect.

The (very) thin red line is the latest overlay we are looking at. The thicker green line is another overlay base on this image :

The 9.0 degrees is an interpretation of the red and green lines. The 12.7 degrees is the slope of the "shadow" over the EV-1. The EV-1 "shadow" is closer to a straight line from the apex, while the other slopes are more more curved (I hope that makes sense).

Base on the slopes I am seeing, I am going to split the difference and say that the "goal" should be an angle of close to 11 degrees (at least for the EV-1).

I think the green original form needs to be shrunk down a smidgeon.We're working with the outer extremities of the image.
As far as the angles go,the intention is to locate the point of interest along the template,then ascertain the actual tangent angle at that point,splitting the point with a straightedge,then using protractor to find the angle.
The drawing I used is 30-inches in length.The closer you get to full scale,the higher the accuracy.
Some angles are given at each 10 % aft-body increment.
-------------------------------------------------------------------------- And remember,the EV-1 is 'dirty' in back.It suffers flow separation at 22-degrees.
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